Tracheal tube introducer-associated airway trauma: a systematic review

BackgroundTracheal tube introducers are recommended in airway management guidelines and are used increasingly as videolaryngoscopy becomes more widespread. This systematic review aimed to summarise the published literature concerning tracheal tube introducer-associated airway trauma.MethodsPubMed, EMBASE and CINAHL databases were searched using pre-determined criteria. Two authors independently assessed search results and performed data extraction and risk of bias assessments.ResultsWe included 16 randomised controlled trials and five observational studies involving 10,797 patients. There was heterogeneity in patient characteristics, airway manipulation, and airway trauma definition and measurement. One study investigated hyperangulated videolaryngoscopy. The standard stylet was the most commonly reported introducer, followed by bougie and stylets with additional features such as video or lighted tip. Airway trauma resulted in low harm and most frequently involved injuries to the upper airway, followed by laryngeal and tracheobronchial injuries. Eighteen studies were comparative and reported a reduction in airway trauma incidence when an introducer was used, with the exception of the standard stylet. Median (IQR [range]) pooled incidence of airway trauma associated with standard stylets was 13.1% (4.2-31.4 [0.5-79.2])% and with bougies was 5.4% (0.4-49.9 [0.0-68.0])%. The risk of bias of included studies was variable and many randomised trials were found to be at high risk due to non-robust measurement of the outcome.ConclusionsStylets might be associated with an increased risk of airway trauma compared with other devices or when no stylet was used, though the quality of evidence is modest. However, other introducers appear to be safe and reduce the risk of airway trauma.